1. Field of the Invention
The present invention relates to an outdoor LED lamp assembly, and more particularly to an outdoor LED lamp assembly used as a road lamp, having a large illumination angle while having no dis-comfort glare or disability glare.
2. Description of Related Art
The technology of light emitting diodes has rapidly developed in recent years from indicators to illumination applications. With the features of long-term reliability, environment friendliness and low power consumption, the LED is viewed as a promising alternative for future lighting products.
As we all know, express roads and major roads must use full cut-off luminaire. An angle of the maximum illuminance of the full cut-off luminaire is varied between 0°˜65°. The maximum permissible illuminance intensities of the full cut-off luminaire in 90° direction and in 80° direction are 10 cd/lm and 30 cd/lm respectively.
A conventional outdoor LED lamp assembly comprises a pair of symmetrical LED lamps. Each LED lamp comprises a heat sink and a plurality of LED modules mounted on a bottom surface of the heat sink. A distribution of light intensity from the outdoor LED lamp assembly has two ways. One way is that an angle of the maximum illuminance of the outdoor LED lamp assembly is varied between 60°˜65°, but the maximum permissible illuminance intensity in 90° direction and in 80° direction is stronger than that of the allowed; thus, the dis-comfort glare or the disability glare is generated. Another way is that the angle of the maximum illuminance of the outdoor LED lamp assembly is varied between 25°˜35°, and the maximum permissible illuminance intensity in 90° direction and in 80° direction are lower than the needed. In this state, the dis-comfort glare or the disability glare does not exist, but light is focused on a small area which has seriously affected the illumination efficiency of the outdoor LED lamp assembly.
What is needed, therefore, is an outdoor LED lamp assembly having a large illumination angle and an anti-glare effect.